Zusammenfassung

Van der Waals clusters of phthalocyanine with 1-4 argon atoms formed inside superfluid helium nanodroplets have been investigated by recording fluorescence excitation spectra as well as emission spectra. The excitation spectra feature a multitude of sharp lines when recorded in superfluid helium droplets in contrast to the resp. spectra measured in a seeded supersonic beam (Cho et al. Chem. Phys. ...

Zusammenfassung

Van der Waals clusters of phthalocyanine with 1-4 argon atoms formed inside superfluid helium nanodroplets have been investigated by recording fluorescence excitation spectra as well as emission spectra. The excitation spectra feature a multitude of sharp lines when recorded in superfluid helium droplets in contrast to the resp. spectra measured in a seeded supersonic beam (Cho et al. Chem. Phys. Lett. 2000, 326, 65). The pickup technique used for doping of the phthalocyanine and the argon into the droplets allows for nondestructive anal. of the cluster sizes. Alternation of the pickup sequence gives information on the binding site of the argon atoms. The investigation of dispersed emission spectra in helium droplets can be used as a special tool for the identification of 000 transitions within the variety of sharp lines seen in the excitation spectra. Thus, different isomers of the clusters can be distinguished. Moreover, the emission spectra reveal information on dynamic processes such as vibrational predissocn. of the van der Waals complexes and interconversion among isomeric species. The binding energy of the phthalocyanine-argon1 complex in helium droplets was estd. to be at most 113 cm-1.